<!DOCTYPE html>
<html lang="zh-CN">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>热点图</title>
    <style>
        body {
            background-color: #333;
        }

        .map {
            position: relative;
            width: 747px;
            height: 617px;
            background: url(map.png) no-repeat;
            margin: 100px auto;
        }

        .beijing {
            position: absolute;
            top: 227px;
            right: 190px;
        }

        .taibei {
            position: absolute;
            top: 500px;
            right: 80px;
        }

        .guangzhou {
            position: absolute;
            top: 536px;
            right: 190px;
        }

        .dotted {
            width: 8px;
            height: 8px;
            background-color: skyblue;
            border-radius: 50%;
        }

        .city div[class^="pulse"] {
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            width: 8px;
            height: 8px;
            box-shadow: 0 0 12px skyblue;
            border-radius: 50%;
            animation: pulse 1s linear infinite;
        }

        .city div.pulse2 {
            animation-delay: .5s;
        }

        @keyframes pulse {
            0% {}

            70% {
                /* scale 会让阴影变大
                transform: scale(4); */
                width: 30px;
                height: 30px;
                opacity: 1;
            }

            100% {
                width: 60px;
                height: 60px;
                opacity: 0;
            }
        }
    </style>
</head>

<body>
    <div class="map">
        <div class="city beijing">
            <div class="dotted"></div>
            <div class="pulse1"></div>
            <div class="pulse2"></div>
        </div>
        <div class="city taibei">
            <div class="dotted"></div>
            <div class="pulse1"></div>
            <div class="pulse2"></div>
        </div>
        <div class="city guangzhou">
            <div class="dotted"></div>
            <div class="pulse1"></div>
            <div class="pulse2"></div>
        </div>
    </div>
</body>

</html>